On 1/15/25 08:28, Jan Kara wrote:
On Wed 15-01-25 17:07:36, Jan Kara wrote:
On Tue 14-01-25 07:01:08, Guenter Roeck wrote:
On 1/14/25 05:19, Jan Kara wrote:
On Mon 13-01-25 15:05:25, Guenter Roeck wrote:
On Thu, Nov 21, 2024 at 06:05:39PM +0800, Jim Zhao wrote:
Address the feedback from "mm/page-writeback: raise wb_thresh to prevent
write blocking with strictlimit"(39ac99852fca98ca44d52716d792dfaf24981f53).
The wb_thresh bumping logic is scattered across wb_position_ratio,
__wb_calc_thresh, and wb_update_dirty_ratelimit. For consistency,
consolidate all wb_thresh bumping logic into __wb_calc_thresh.
Reviewed-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Jim Zhao <jimzhao.ai@xxxxxxxxx>
This patch triggers a boot failure with one of my 'sheb' boot tests.
It is seen when trying to boot from flash (mtd). The log says
...
Starting network: 8139cp 0000:00:02.0 eth0: link down
udhcpc: started, v1.33.0
EXT2-fs (mtdblock3): error: ext2_check_folio: bad entry in directory #363: : directory entry across blocks - offset=0, inode=27393, rec_len=3072, name_len=2
udhcpc: sending discover
udhcpc: sending discover
udhcpc: sending discover
EXT2-fs (mtdblock3): error: ext2_check_folio: bad entry in directory #363: : directory entry across blocks - offset=0, inode=27393, rec_len=3072, name_len=2
Thanks for report! Uh, I have to say I'm very confused by this. It is clear
than when ext2 detects the directory corruption (we fail checking directory
inode 363 which is likely /etc/init.d/), the boot fails in interesting
ways. What is unclear is how the commit can possibly cause ext2 directory
corruption. If you didn't verify reverting the commit fixes the issue, I'd
be suspecting bad bisection but that obviously isn't the case :-)
Ext2 is storing directory data in the page cache so at least it uses the
subsystem which the patch impacts but how writeback throttling can cause
ext2 directory corruption is beyond me. BTW, do you recreate the root
filesystem before each boot? How exactly?
I use pre-built root file systems. For sheb, they are at
https://github.com/groeck/linux-build-test/tree/master/rootfs/sheb
Thanks. So the problematic directory is /usr/share/udhcpc/ where we
read apparently bogus metadata at the beginning of that directory.
Ah, the metadata isn't bogus. But the entries in the directory are
apparently byte-swapped (little vs big endian). Is the machine actually
little or big endian?
sheb is big endian. I only see the problem there, not with the little endian
emulation. But that uses a different root file system. As I just mentioned
in the other reply, it might well be an emulation bug, but it is odd that your
patch would be required to expose that.
Guenter
